Minor Feature update, stability fixes

Changelog:

• Internal CryptoPP Version updated to 7.0.0
• Moved messages into static lib to speed up compile time
• Fixed bug where messages could be processed out of order, leading to reconnect loops
• Make ECC the default for new crypto setups
• Clearing a datastore will now emit changed for every removed item instead of the generic clear signal (for consistent behaviour, as this was already the case for synchronization)
• Fixed caching for changes from passive to passive instance
• Fixed bug where setting an empty device name renders an account unusable
• Use exception to report "default resolving" on generic conflict resolvers
• Added public method the get a keystore instance
• Added multi-column support to datastore model to make it usable with table/tree views
• Added support to directly import an account from the setup. This speeds up adding an account
• Updated qdsapp to use the QtService framework
  • Supports advanced service control, like reloading
  • Supports socket activation
  • Can be installed as system service
• Updated docker image based on alpine linux for a smaller image
• Improve wait semantics for the passive setup creation
• Fixed cleanup of engine threads and databases to prevent lifelocks